feat: Clip effects, asset sorting, and timeline improvements

Major features and improvements:

* **Clip Effects**:
  * Added UI in Properties Panel to manage effects on video/image clips (add, remove, toggle, reorder).
  * Implemented dynamic parameter fields for effects.
  * Added support for keyframing effect parameters.

* **Assets Panel**:
  * Added sorting options: Name, Type, Duration, and File Size.
  * Persisted view preferences (grid/list mode, sort order) to local storage.
  * Refactored media item rendering and drag interactions.

* **Timeline & Interaction**:
  * **Keyframe Dragging**: Added ability to drag keyframes directly on the timeline element.
  * **Resizing**: Improved resize logic to respect neighboring clips (prevents overlaps).
  * **Visuals**: Implemented tiled background rendering for video/image clips on the timeline.
  * **Shortcuts**: Added "Deselect All" action bound to the `Escape` key.
  * **Fixes**: Corrected drag-and-drop coordinate calculations when the timeline track area is scrolled.

* **Text Elements**:
  * Refactored text background storage to use an explicit `enabled` flag.
  * Added `V8toV9` storage migration to update existing projects.

* **Architecture**:
  * Moved export state management to `ProjectManager` for better lifecycle handling.
  * Refactored `PropertiesPanel` sections to be more composable (custom headers, borders).

1 files changed, 84 insertions, 0 deletions

diff --git a/apps/web/src/lib/commands/timeline/element/keyframes/upsert-effect-param-keyframe.ts b/apps/web/src/lib/commands/timeline/element/keyframes/upsert-effect-param-keyframe.ts
new file mode 100644
index 00000000..f5236279
--- /dev/null
+++ b/apps/web/src/lib/commands/timeline/element/keyframes/upsert-effect-param-keyframe.ts
@@ -0,0 +1,84 @@
+import { EditorCore } from "@/core";
+import { Command } from "@/lib/commands/base-command";
+import { upsertEffectParamKeyframe } from "@/lib/animation/effect-param-channel";
+import { updateElementInTracks } from "@/lib/timeline";
+import { isVisualElement } from "@/lib/timeline/element-utils";
+import type { TimelineTrack } from "@/types/timeline";
+
+export class UpsertEffectParamKeyframeCommand extends Command {
+	private savedState: TimelineTrack[] | null = null;
+	private readonly trackId: string;
+	private readonly elementId: string;
+	private readonly effectId: string;
+	private readonly paramKey: string;
+	private readonly time: number;
+	private readonly value: number;
+	private readonly interpolation: "linear" | "hold" | undefined;
+	private readonly keyframeId: string | undefined;
+
+	constructor({
+		trackId,
+		elementId,
+		effectId,
+		paramKey,
+		time,
+		value,
+		interpolation,
+		keyframeId,
+	}: {
+		trackId: string;
+		elementId: string;
+		effectId: string;
+		paramKey: string;
+		time: number;
+		value: number;
+		interpolation?: "linear" | "hold";
+		keyframeId?: string;
+	}) {
+		super();
+		this.trackId = trackId;
+		this.elementId = elementId;
+		this.effectId = effectId;
+		this.paramKey = paramKey;
+		this.time = time;
+		this.value = value;
+		this.interpolation = interpolation;
+		this.keyframeId = keyframeId;
+	}
+
+	execute(): void {
+		const editor = EditorCore.getInstance();
+		this.savedState = editor.timeline.getTracks();
+
+		const updatedTracks = updateElementInTracks({
+			tracks: this.savedState,
+			trackId: this.trackId,
+			elementId: this.elementId,
+			elementPredicate: isVisualElement,
+			update: (element) => {
+				const boundedTime = Math.max(0, Math.min(this.time, element.duration));
+				const animations = upsertEffectParamKeyframe({
+					animations: element.animations,
+					effectId: this.effectId,
+					paramKey: this.paramKey,
+					time: boundedTime,
+					value: this.value,
+					interpolation: this.interpolation,
+					keyframeId: this.keyframeId,
+				});
+				return { ...element, animations };
+			},
+		});
+
+		editor.timeline.updateTracks(updatedTracks);
+	}
+
+	undo(): void {
+		if (!this.savedState) {
+			return;
+		}
+
+		const editor = EditorCore.getInstance();
+		editor.timeline.updateTracks(this.savedState);
+	}
+}